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arXiv · 2003.05186

Finite cubic graphs admitting an cyclic group of automorphisms with at most three orbits on vertices

Primoz Potocnik·Micael Toledo
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Abstract

The theory of voltage graphs has become a standard tool in the study graphs admitting a semiregular group of automorphisms. We introduce the notion of a cyclic generalised voltage graph to extend the scope of this theory to graphs admitting a cyclic group of automorphism that may not be semiregular. We use this new tool to classify all cubic graphs admitting a cyclic group of automorphisms with at most three vertex-orbits and we characterise vertextransitivity for each of these classes. In particular, we show that a cubic vertex-transitive graph admitting a cyclic group of automorphisms with at most three orbits on vertices either belongs to one of 5 infinite families or is isomorphic to the well-know Tutte-Coxeter graph.

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Primoz Potocnik, Micael Toledo. 2020-03-11. Finite cubic graphs admitting an cyclic group of automorphisms with at most three orbits on vertices. https://arxiv.org/abs/2003.05186

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